This invention relates to a single-reel type tape cartridge for use with magnetic recording-reproducing apparatus and, more particularly, to improvements in the tape leader of a tape cartridge of this type.
Single-reel type tape cartridges are extensively used in computer backup and other data storage applications for safekeeping. With a tape cartridge of this type, a leader tape or leader member attached to the outer end of a magnetic tape is drawn out by drawing-out means provided in a magnetic recording-reproducing apparatus (hereinafter referred to as a xe2x80x9crecorderxe2x80x9d) or drive, the tape is led through passages in the recorder, and the tape end is fixed to the hub of another reel normally held within the recorder. On conclusion of recording or playback operation the tape is driven backward and withdrawn into the cartridge, until the leader tape is reset in the original position in the cartridge.
Typical of leader members for conventional single-reel type tape cartridges is one (disclosed, e.g., in Japanese Patent Application Kokai No. 58-169380) which comprises a pin, block, etc. secured to a tape end to be caught by a tape drawing-out member of a recorder. Another type uses a leader tape of relatively tough, elastic material which is connected to a magnetic tape end and has a hole at its own outer end adapted to be engaged with a corresponding hook of a drawing-out member of a recorder which too is formed of a relatively tough, elastic material (Japanese Patent Application Kokai No. 10-188520). When the cartridge incorporating the latter is not in use, the leader tape is held within the cartridge housing and the engaging hole of the leader tape is engaged with a hook inside the housing.
FIG. 10 is an exploded view of a conventional single-reel type cartridge 103 described in the specification of the above-mentioned Patent Application Kokai No. 10-188520. A housing of the cartridge including an upper casing 101 and a lower casing 102 is shown containing a single tape reel 107 which has an upper flange 104 and a lower flange 105, the tape reel 107 being normally biased toward the lower door lock member 102 by a compression spring 108. A leader tape 109 is spliced to the outer end of a length of magnetic tape 106 wound round a hub (not shown) of the upper flange 104 of the tape reel 107. The tape reel 107 has a bearing (not shown) on a ring which is press fitted in an annular recess (not shown) formed in the center of the upper flange 104. With a reel shaft (not shown) fitted in the bearing, the reel can revolve around the shaft. The upper flange 104 of the tape reel 107 has a serration 114 formed along its circumference. On the other hand, a pair of brake members 112, 113 are provided on the inner surface 101a of the upper casing 101 and are normally biased toward the serration 114 by torsion coil springs 110, 111, with cogs 115, 116, respectively, of the brake members 112, 112 adapted to be in mesh with the serration to keep the tape reel from revolution when the cartridge is not in use. When the cartridge is on standby the magnetic tape 106 is wound up on the tape reel 107, and an engaging hole formed at the end of the leader tape 109 is engaged with a hook 117 located close to a side wall of the cartridge housing 103. An opening through which the magnetic tape 106 is drawn out from the cartridge housing 103 is normally closed by a lid 118 which is openable with respect to the cartridge housing.
For use, the cartridge is loaded into a recorder, and the brake members 112, 113 are automatically set free and the tape reel 107 is lifted against the urging of the compression spring 108 to a position free to turn. At the same time, the lid 118 is opened by means provided for that purpose in the recorder.
The tape drawing-out member on the part of the recorder then enters the housing through the opening to be engaged with the hole of the leader tape 109 and draws out the magnetic tape together with the leader tape 109 in the manner described above, so that the tape is threaded in the route within the recorder. When the cartridge is not in use, the magnetic tape is housed within the cartridge and the leader tape is wound up too, with its engaging hole engaged with the hook 117.
The leader tape 109 is made using a thick spring sheet of tough synthetic resin such as polyethylene terephthalate (PET). As FIGS. 11(a) to 11(c) indicate, a hole 128 is formed at the end of the tape so as to be engaged with a tab 121 (serving as a hook) formed at the end of a tape drawing-out member 122 of the recorder. The hole 128 has an angular cutout 123 to ensure positive engagement with the tab 121, with a neck of the drawing-out member that supports the tab 121 fitted in the cutout. FIGS. 11(a) to 11(c) show a sequence of the stages in which the drawing-out member 122 is progressively engaged with the leader tape 109 as the drawing-out member enters the cartridge.
The tape drawing-out mechanism of the prior art causes the following problem. The tape drawing-out member 122 of the recorder, as shown in FIGS. 11(a) to 11(c), is in the form of a tape connected to a reel provided in the recorder, with the tape end having the tab 121 adapted to be engaged with the hole 128 of the leader tape in the tape cartridge. Since the end portions of the leader tape and the drawing-out member 122 of the recorder are both tape-shaped, they are susceptible to curling. When they both curl, it becomes sometimes impossible for the tape drawing-out member 122 of the recorder to engage the leader tape 109 of the cartridge loaded in the recorder.
On the other hand, direct coupling of the end of a magnetic tape to a tough leader member without the aid of a leader tape would stabilize the actions of drawing out and drawing in of the magnetic tape. Such a leader member, as illustrated in FIG. 1, comprises a center pin member 91 in the form of a pin on which a tape end is wound and secured in place by clamping, and a pair of engaging members 92, 92 fixed at one ends to the upper and lower end of the pin member 91. On the sides of the engaging members 92, 92 facing each other, there are formed engaging recesses 92-1, 92-2 in mirror symmetry (see FIG. 9) adapted to engage a pin or casing of a recorder. The center pin member 91 is made of metal and the engaging members 92, 92 are made of plastic.
Users generally desire to enjoy recording and playback with both tape cartridges using a leader tape and a leader member on one and the same drive device. On the other hand, tape cartridge manufacturers commonly desire to minimize the investment in equipment to manufacture the two types of tape cassettes.
The tape cartridge according to the present invention is one including a single tape reel around which a length of magnetic tape is wound and which is turnably held within a housing in such a manner that the beginning of the tape is drawn out through an opening formed in the housing by a tape drawing-out member of a recorder, said drawing-out member having an engaging means at the outer end, characterized in that the housing has both a cell in which a hook member to catch an engaging end of a leader tape, when the leader tape holding the beginning of the magnetic tape is used, is detachably fitted and a cell in which a leader member to hold the beginning of the magnetic tape, when the leader member is used, is contained.
In another aspect the tape cartridge according to the invention includes a single tape reel around which a length of magnetic tape is wound and which is turnably held within a housing in such a manner that the beginning of the tape is drawn out through an opening formed in the housing by a tape drawing-out member of a recorder, said drawing-out member having an engaging means at the outer end, said housing having a cell in which a hook member to catch an engaging end of a leader tape holding the beginning of the magnetic tape is detachably fitted, characterized in that the housing is made using a mold equipped with either a first replaceable mold part for forming a cell in which a leader member holding the beginning of the magnetic tape is contained or a second replaceable mold part that can replace the first mold part but does not form the cell to contain the leader member.